Carton



April 25, 1967 N. H. MOORE ETAL CARTON 2 Sheets-Sheet 1 Filed June 9, 1965 R m5 m 1 N R E .M 0 V H 7 W NM n @i April 25, 1967 N. H. MOORE ETAL. 3,315,871

CARTON Filed June 9, 1965 2 Sheets-Sheet 2 l 6. lNl/EN 70% J THOMAS K FOSTER NORMA/V {ff/MOORE BYJW ATTOR/VE Vs United States Patent 3,315,371 CARTON Narman H. Moore and Thomas W. Foster, Palo Alto, Calif, assignors to Fibrehoard Paper Products Corporation, San Franicsco, Calif, a corporation of Delaware Filed .lune 9, 1965, Ser. No. 462,589 9 Claims. (Cl. 22937) This invention relates to a carton and more particularly relates to a carton adapted to be fully sealed and expeditiously opened to dispense frozen foods or like goods therefrom.

The availability of heat scalable adhesives or coatings has encouraged the packaging art to supplement and oftentimes dispense with the use of conventional multi-structured packages for the purpose of packaging frozen foods and the like. Such conventional packages may comprise, for example, a paperboard carton having a waxed or otherwise suitably coated paper overwrap employed to prevent contamination and leakage. The advent of the above-mentioned heat scalable coatings, such as polyethylone, has made it feasible to apply the coating directly onto a paperboard carton for the purpose of sealing the end flaps thereof.

The utilization of such an adhesively treated carton has given rise to problems including the provision of a carton end closure capable of being tightly sealed and yet readily opened to dispense the carton contents. This invention substantially overcomes such problems by constructing and arranging the end flaps of the carton so that the corners thereof, whereat the primary sealing problem occurs may be slightly crushed during packaging to effect an efficient seal. Furthermore, the flaps are arranged to permit the carton to be opened expeditiously when so desired.

An object of this invention is to provide a carton blank which may be erected to form a tightly sealed carton which may be readily opened.

A further object of this invention is to provide a carton comprising at least one corner constructed and arranged to be slightly crushed during packaging to effect an efficient seal.

A still further object of this invention is to provide a fully sealed carton end closure which may be opened expeditiously.

Further and more specific objects of this invention will become apparent from the following description and accompanying drawings wherein:

FIG. 1 is a perspective view of a closed and sealed carton employing novel features of this invention,

FIG. 2 is an enlarged view illustrating a sealed corner of the carton of FIG. 1;

FIG. 3 is a view taken on line III-III in FIG. 1;

FIG. 4 is a view similar to FIG. 1 disclosing the carton as it would appear with the top end closure thereof opened;

FIG. 5 is a cross-sectional view taken on lines V-V in FIG. 1; and

FIG. 6 is a top plan View of a blank utilized to form the carton illustrated in FIGS. 14.

The closed and sealed carton of FIG. 1 may be formed out of the blank illustrated in FIG. 6 by suitable packaging techniques. For example, US. patent application Ser. No. 457,893 by John D. Winters et al. for an Apparatus and Method for Folding and Sealing Cartons discloses machinery and method steps which may be employed to form the type of carton illustrated.

The blank preferably comprises a paperboard coustituent fully coated on both sides with a laminant plastic such as polyethylene, polyvinylidene chloride or other suitable heat sensitive coating which will react (melt) at temperatures within a range of from 200 to 600 F. Alternatively, such a coating could be applied selectively to the portions of the carton to be sealed. Also a heat seal wax, i.e., a wax coating which has been formulated to accelerate solidification thereof in a short time interval may be utilized.

Furthermore, depending upon the particular carton application a pre-applied thermoplastic adhesive, applied during or before the carton manufacturing operation, may be employed. For the purpose of the following discussions the above briefly described conventional coatings will be described as heat scalable coatings or simply adhesives. The particular adhesive chosen should, of course, afford the two-fo1d function of securing the flaps together and sealing the end closure to prevent carton content contamination or leakage.

The blank of FIG. 6 comprises parallel first scorelines defining first and second side panels 11 and 12, respectively, having end panels 13 and 14 hingedly connected thereto in the manner shown. A manufacturers glue flap 15 is arranged to be secured to the inner Wall of end panel 14, as clearly illustrated in FIG. 5, to form the carton into a tubular configuration for shipping purposes. Alternatively, flap 15 may be formed as an extension of end panel 14 and suitably secured to side panel 11.

Bottom closure flaps Illa-14a are suitably connected to one end of their respective side and end panels by a longitudinally extending scoreline 16-, arranged transversely with respect to the first scorelines. As will be hereinafter explained, these flaps may be suitably folded into superimposed relationship and sealed together to form a carton bottom closure.

Longitudinally extending scoreline 17, arranged in parallel relationship with respect to and forming a pair of second score'lines with scoreline 16, hingedly connects first through fourth top closure flaps 11b-14h to a second end of their respective side and end panels. First flap 11b has a greater width than second flap 12b. Scoreline 17 is interrupted by cuts or first cut means 12c and 120! formed in side panel 12, preferably offset transversely away from scoreline 17. Similar cuts may be formed on panel 11, adjacent scoreline 16, in the manner illustrated. These cuts are of limited depth and assure a slight crushing of the corners of the formed top closure to effect an efficient seal thereat, as will be hereinafter more fully understood.

The underside of flap 11b has a cut 110 of limited depth formed therein, as viewed in FIGS. 5 and 6. Side edges 11d and Me of flap 1112 are preferably arranged to converge towards each other slightly in the manner illustrated. A perforated line 13c defines a removable tab 13d formed in panel 13 to facilitate opening of the carton end closure to the FIG. 3 position. Preferably, such perforations do not extend through panel 13 so as to assure an air-tight closure.

As above described, the carton is initially formed by securing manufacturers glue flap 15 to the inside of panel 14 to thus form a tubular structure which may be economically shipped and thereafter stacked in a carton feeder. In the embodiment illustrated, the bottom closure is formed as follows: minor flap 11a is folded; end flaps 13a and 14a are folded onto flap 11a; major flap 12a is folded over the previously folded flaps; and the flaps are adhered together in sealed relationship by a suitable sealing means. Such a sealing means preferably comprises a heat and pressure sealing means of the type disclosed in the above-mentioned application.

The top flaps are held in an open position to facilitate filling of the partially formed carton with contents, such as free flowing frozen foodstuff. Thereafter, the top closure is formed in the following manner: second flap 12b is folded; third and fourth flaps 13b and 14b are folded over flap 12b; first flap 11b is folded over the afore-mentioned flaps, and the flaps are secured together by a suitable sealing means. The formed carton thus comprises opposed side panels 11-12, opposed end panels 1314 and top and bottom closures.

Alternatively, fiaps 13b and 14b could be folded first with flap 12b and then flap 11b folded thereon in sealing relationship. The bottom closure could also be folded in such an alternative manner.

As above stated, novel aspects of this invention constitute the construction and arrangement of cuts or first cut means 120 and 12d. These cuts are identical to the ones formed in panel 11 and therefore the following discussions also apply to the latter cuts.

The cuts are arranged adjacent each corner of the top closure whereat second flap 12b hingedly connects to second side panel 12 to permit the corners of the end closure to be slightly crushed when overlying portions of flap 11b are forced into sealing relationship with the underlying flaps. This arrangement is illustrated in enlarged and somewhat exaggerated FIGS. 2 and 3. As more clearly illustrated in FIG. 3, the top surface of flap 13b is thus arranged to substantially lie in the same pla'ne as the top surface of flap 12b.

It has been found that one of the primary sealing problems encountered, pursuant to the packaging of frozen foodstuffs, for example, constitutes the inability to consistently effect an etficient seal at the corners thereof. Experimentation has shown that by arranging cuts 12c and 12d in the manner illustrated and by extending them into panel 12 to a limited depth, i.e., at least through the carton coating and preferably to a depth approximating one-half of the thickness of panel 12, will substantially eliminate the above problem. Although the cuts are preferably offset slightly from scoreline 17, it should be understood that such cuts could be formed directly upon scoreline 17 in certain applications.

Therefore, it should be further understood that when such a cut is herein stated as formed on a panel that such statement includes formation of the cut in the offset manner illustrated or directly upon scoreline 17. Also, in certain applications such cut could be formed off panel 13 or 14 in a like manner. The preferred ratio of the length of each cut to the width dimension of panel 12 is within the range of from 1:32 to 1:8. For example, a ratio of 1:16 has afforded the above-mentioned sealing desiderata for a particular carton application.

Cut 110 is constructed and arranged in the manner illustrated in FIGS. and 6 to facilitate opening the top end closure of the carton to the position disclosed in FIG. 4. A serious opening problem prevails in connection with the packaging of frozen food in the type of carton herein described, due to the fact that conventional opening means oftentimes do not insure against contamination and leakage. Furthermore, the inherent toughness of polyethylene and like coatings renders it impracticable to use such conventional opening means.

The cut preferably extends to a sutficient depth on the underside of first fiap 11b to carry it through the polyethylene or like coating, but may be arranged to further extend into the paperboard. The paperboard may comprise several plies or a homogeneous Fourdrinier sheet. It has been found that when a polyethylene coating is employed that it is sufficient if the cut extends only through such coating. The resulting tear will appear as 11g illustrated in FIG. 4, i.e., such tear will take place between the above coating and the surface portions of panel 11b which are adhered to fiap 12b.

Cut 110 is preferably shaped to comprise a first or tapered portion arranged in diverging relationship with respect to free edge 11 of flap 11b, a second or straight portion and a third or arcuate portion arranged to extend towards scoreline 17. The arcuate portion of the cut facilitates the substantially right angle change in direction of the tear, i.e., transversely with respect to the second, straight portion of the cut.

When tab portion 13d, formed by perforated line 13c, is manually punched and lifted to open the carton end closure, tapered edge 132 aids in directing the opening force towards and along the first portion of the cut. Such force is then directed along the cuts second portion and to the third portion towards scoreline 17. The adhesive securement of one side of panel 11b to flap 12b assures a cleanly defined tear.

Alternative embodiments of out He may be employed, depending upon the particular type of carton to be formed. For example, the third cut portion could be removed and the second straight cut portion extended and terminated at the free edge of flap 14b (FIG. 5). In actual practice it was found that the last-mentioned cut embodiment substantially provided a cleanly defined tear along the modified second cut portion and the free edge of flap 14b to scoreline 17. It can be seen, however, that the third, arcuate cut portion of the illustrated embodiment more readily facilitates the above-described right angle change in direction of the tear.

We claim:

1. A carton comprising opposed side and end panels and top and bottom closures, said top closure comprising a first flap hingedly connected to a first one of said side panels a second flap of less width than said first flap hingedly connected to the second one of said side panels and third and fourth fiaps hingedly connected to said opposed end panels, first cut means formed on said second side panel at each corner of said top closure said first cut means being in parallel and in slightly offset relationship to a score line hingedly connecting said second flap to said second side panel, second cut means formed on an underside of said first flap, each of said first and second cut means arranged to extend into their respective panel or flap to a limited depth, means adhesively securing inner surface portions of said first flap in overlying relationship with respect to said second fiap adjacent said second cut means for permitting part of said inner surface of said first flap portion to remain secured to said second flap when said first flap is detached from said second flap, said first cut means constructed and arranged on the carton side walls to permit a slight crushing of the corner portions of said first and second flaps and said second side panel and cooperate with said third and fourth flaps to effect etficient sealing thereat.

2. The invention of claim 1 wherein said second cut means is continuous and comprises a first out portion arranged to intersect a free edge of said first flap and further arranged in diverging relationship therewith, a second portion substantially coinciding with a free edge of said second fiap and a third portion arranged to extend towards a scoreline hingedly connecting said first flap to said first side panel.

3. A carton end closure comprising opposed first and second panels and opposed end panels each having a flap hingedly connected thereto by a scoreline, at least one cut means formed on said second panel adjacent to a corner of said end closure where said second flap hingedly connects to said second panel, said cut means being in parallel and slightly offset relationship to the scoreline hingedly connecting said second flap to said second panel, said cut means extending into said second panel to a limited depth, the flap of said first panel adhesively secured to the flap of said second panel in overlying relationship thereto and further arranged with said cut means to slightly crush the corner of said end closure and cooperate with a flap connected to said end panel to effect efiicient sealing thereat.

4. A carton end closure comprising opposed first and second panels, first and second flaps hingedly connected to said first and second panels, respectively, said first flap having a width greater than said second flap and further having surface portions adjacent a free edge thereof adhesively secured in overlying relationship to said second flap, and out means of limited depth formed on the underside of said first flap, said out means being in part adjacent and parallel to a free edge of said second flap for permitting a portion of said first flap to remain secured to said second flap when said carton is opened.

5. The invention of claim 4 further comprising opposed third and fourth panels connected to said first and second panels and each having a flap connected thereto, said last mentioned flaps adhesively secured beneath said first flap, said third panel having a removable tap formed therein adjacent the flap connected to said third panel to facilitate opening of said end closure, said third flap having an edge thereof arranged to direct a force, utilized to remove the tap, toward said out means.

6. The invention of claim 4 wherein said cut means is continuous and comprises a first cut portion arranged to intersect a free edge of said first flap and further arranged in diverging relationship therewith, a second portion substantially coinciding with a free edge of said second fiap and an arcuate portion arranged to extend towards a scoreline hingedly connecting said first flap to said first panel.

7. A one-piece carton blank comprising parallel first scorelines arranged to serially define a first side panel, a first end panel, a second side panel, a second end panel and a pair of parallel second scorelines arranged transversely with respect to said first scorelines to form closure flaps hingedly connected to each end of each panel, at least one cut means formed on one of said panels, said out means on said panel being arranged in parallel and slightly oifset relationship to the second scoreline which hingedly connects one of said closure flaps to said panel and being adjacent to one of the first scorelines which defines the panel, said cut means arranged to extend into said one panel to a limited depth and further arranged to effect a slight crushing of a corner of an end closure when a carton is formed.

8. A one-piece carton blank coated with a heat sealable coating comprising parallel first scorelines arranged to serially define a first side panel, a first end panel, a second side panel, a second end panel and a pair of parallel second scorelines arranged transversely with respect to said first scorelines to form closure flaps hingedly connected to each end of each panel, the flap on a first of said side panels being of a width equal to the length of the end panels, the other of said flaps on said side panels being of a width substantially less than the length of said end panels continuous cut means formed on the flaps on said first side panel, said out means arranged to a depth at least through the coating on said flap and including a straight portion extending from a free edge of said flap parallel to the scoreline which hingedly connects said flap to its side panel, said portion of said out further constructed and arranged to overlie and substantially coincide with a free edge of the flap connected to a second of said side panels when the blank is formed into a closed carton.

9. The invention of claim 8 wherein said cut means includes a portion arranged to intersect in diverging relationship the free edge of said flap on said first panel and another portion which is arcuately shaped and arranged to extend from said straight portion toward the scoreline connecting said flap to said first side panel.

References Cited by the Examiner UNITED STATES PATENTS 2,015,148 9/1935 Knowlton.

2,272,203 2/1942 Hothersall 229-17 2,588,996 3/1952 Snyder 229-17 2,751,136 6/1956 Moore 229-17 3,098,600 7/1961 Hagan et a1. 229-37 3,136,471 6/1964 Brastad 22917 3,197,109 7/ 1965 Nelson 2 29-37 3,214,079 8/ 1965 Andrews et a1 229-37 3,262,630 7/1966 Koolnis 229-17 JOSEPH R. LECLAIR, Primary Examiner. DAVIS T. MOOREHEAlD, Examiner. 

1. A CARTON COMPRISING OPPOSED SIDE AND END PANELS AND TOP AND BOTTOM CLOSURES, SAID TOP CLOSURE COMPRISING A FIRST FLAP HINGEDLY CONNECTED TO A FIRST ONE OF SAID SIDE PANELS A SECOND FLAP OF LESS WIDTH THAN SAID FIRST FLAP HINGEDLY CONNECTED TO THE SECOND ONE OF SAID SIDE PANELS AND THIRD AND FOURTH FLAPS HINGEDLY CONNECTED TO SAID OPPOSED END PANELS, FIRST CUT MEANS FORMED ON SAID SECOND SIDE PANEL AT EACH CORNER OF SAID TOP CLOSURE SAID FIRST CUT MEANS BEING IN PARALLEL AND IN SLIGHTLY OFFSET RELATIONSHIP TO A SCORE LINE HINGEDLY CONNECTING SAID SECOND FLAP TO SAID SECOND SIDE PANEL, SECOND CUT MEANS FORMED ON AN UNDERSIDE OF SAID FIRST FLAP, EACH OF SAID FIRST AND SECOND CUT MEANS ARRANGED TO EXTEND INTO THEIR RESPECTIVE PANEL OR FLAP TO A LIMITED DEPTH, MEANS ADHESIVELY SECUR- 